The present invention pertains generally to agricultural product processing methods and devices and, more particularly, to devices and methods for snipping the ends off of beans, and knife assemblies for use in such devices.
Beans, such as green beans, as harvested have a central edible pod with blossom and stem ends. The ends of the beans are fibrous, and, therefore, are not tender and thus not palatable to consumers of the beans. Therefore, prior to canning or other packaging of such beans for marketing, it is essential to remove as many of the stem and blossom ends from the harvested beans as possible.
Specialized machines, known as bean snippers, have long been used to remove the ends from large quantities of harvested beans prior to canning or other packaging of the beans. A conventional bean snipper includes an elongated hollow drum which is rotatably mounted on a frame such that the drum extends in a generally horizontal direction with a bean input end of the drum elevated slightly with respect to the other output end thereof. A plurality of circumferentially extending slots are formed on the drum, extending through the drum from the interior to the exterior thereof. The slots are sized and shaped to allow the narrow ends of beans to protrude therethrough from the interior to the exterior of the drum, while preventing the beans themselves from falling out of the drum through the slots. The interior of the drum is divided by axially spaced apart partitions. The partitions within the interior of the bean snipper drum are spaced apart from each other by a distance which is slightly smaller than the typical length of the beans to be processed by the bean snipper, and include central apertures which allow beans to flow through the drum from the elevated input end thereof to the opposite output end thereof as the drum is rotated.
As the bean snipper drum is rotated, beans within the drum are lifted from the inside bottom of the drum and fall back into pockets formed between the partitions therein. The spacing of the partitions within the drum helps to direct the blossom and stem ends of the beans to protrude through the slots formed in the wall of the drum. A plurality of snipper knives are mounted on the outside of the drum, adjacent to the peripheral surface thereof. The snipper knives cut the non-tender blossom and stem ends, which protrude through the slots, from the beans as the drum rotates the slots past the snipper knives. In the random travel of beans from one end of the snipper drum to the other, as the drum is rotated, most of the beans in the drum will have each of their blossom and stem ends protrude through a slot, to be cut off by a snipper knife. Thus, the conventional bean snipper device described is highly effective in removing the undesirable ends from large quantities of beans. Various known devices and structures may be placed within the bean snipper drum to increase snipping efficiency.
Various different types of snipper knives are used in combination with the conventional bean snipper device described above to cut the bean ends which protrude from the slots formed in the drum from the beans. For example, bean snipper knives may be formed as elongated bands of steel having sharpened edges, or having several cutouts or openings with sharpened edges, which are mounted wrapped around the outer peripheral surface of the rotating bean snipper drum in a fixed position, as shown, for example, in U.S. Pat. No. 4,213,383. More commonly, a plurality of bean snipper knife assemblies are mounted adjacent to the outer peripheral surface of the bean snipper drum on a plurality of mounting rods which are attached to the bean snipper drum frame and which extend in an axial direction parallel to the outer surface of the drum. Such knife assemblies typically include a knife head attached to a resilient flexible means, such as a leaf spring or semi-flexible metal knife rod which, in turn, is attached to the mounting rod positioned external and parallel to the bean snipper drum by a knife assembly holder or bracket. The mounting rods on which the knife assemblies are mounted may be fixed or may be oscillated, thereby to oscillate the knife heads of the knife assemblies back and forth in an axial direction against the outer periphery of the bean snipper drum. If a sufficient number of banks of knife assemblies are provided, such that each slot formed in the drum will pass by the cutting edge of at least one knife head during rotation of the drum, maximum bean snipping efficiency can be achieved without requiring such oscillation of the knife assemblies. The knife heads employed in the knife assemblies may have various forms. For example, a bean snipper knife head may include several knives supported on a structure, such as a rigid bar. A more common knife head is triangular in shape, with two cutting edges formed thereon.
A typical knife assembly holder for attaching a knife assembly to a mounting rod is formed as a split cylindrical sleeve, made of metal or plastic, having semi-cylindrical complimentary parts which are positioned around the mounting rod positioned parallel to the snipper drum. The split cylindrical sleeve typically has lugs formed extending therefrom, through which screws, bolts, or other fasteners are used to join the two parts of the sleeve together to secure the sleeve to the mounting rod. Typically, a separate fastener or fasteners are used to secure the resilient flexible leaf spring or knife rod connecting the knife head to the knife assembly holder to the holder. For example, an aperture or clamping structure may be formed on one of the semi-cylindrical complimentary parts forming the split cylindrical sleeve of the holder and adapted to receive an end of a knife rod opposite to the end thereof which is attached to the knife head. A bolt, screw, or other fastener may be used to hold the end of the knife rod in position within the aperture or clamping structure. By properly adjusting the position of the split cylindrical sleeve holder on the mounting rod, and the position of the knife rod on the holder, a desired amount of pressure of the knife head against the snipper drum periphery may be achieved to ensure that the blades on the knife head remain in contact with the drum periphery for effective bean snipping, while minimizing damage to the drum by excessive pressure of the knife head against the rotating drum. A manual cam lever may be provided on the knife assembly holder to engage the knife leaf spring or rod to bow it towards the drum, thereby also to adjust the pressure of the knife head against the drum. Conventional bean snipper knife assemblies and holders therefor of this type are described and illustrated, for example, in U.S. Pat. Nos. 3,304,974, 3,318,350, 3,378,051, 3,885,697, 4,981,073, and 5,144,887.
Before operation of a conventional bean snipper, as described above, it is necessary to mount many snipper knife assemblies onto the mounting rods positioned along side the snipper drum. During operation of the snipper device, it is often necessary to replace worn knife heads and blades, and to adjust the position of the knife assemblies, e.g., to adjust the pressure of the knife head against the outer periphery of the drum, e.g., as the drum periphery and/or knife blades becomes worn, and/or has the resiliency of the leaf spring or knife rod which connects the knife head to the knife assembly holder changes. Such changes and adjustments during operation of the bean snipper device are typically performed in uncomfortable and often messy conditions. Often times, an operator must position himself at least partially under an operating bean snipper to make such adjustments. With a conventional knife assembly holder, e.g., employing split cylindrical sleeves having semi-cylindrical complementary parts held together by a plurality of fasteners, such as screws and bolts, and with separate fasteners for mounting the flexible leaf spring or knife rod connected to the knife head to the knife assembly holder, the process of removing, adjusting, and remounting a snipper knife assembly can take several minutes, and, typically, requires several tools, e.g., wrenches, pliers, screwdrivers, etc. Since a typical conventional bean snipper may have many such knife assemblies, e.g., thirty or more, mounted thereon, the total time spent removing, adjusting, and reattaching knife assemblies using conventional knife assembly holders in such a system, to maintain optimal bean snipping efficiency, can be significant.
What is desired, therefore, is a knife assembly holder and method which allows an operator of a bean snipper, or similar agricultural product processing device, to remove, adjust, and remount a knife assembly in a reduced amount of time, and, preferably, by hand, without the use of tools.
The present invention provides a holder for mounting a knife assembly, for use, e.g., in a bean snipper or similar agricultural product processing device, to a mounting rod or shaft, positioned adjacent to the device, easily, quickly, and securely. Preferably, a snipper knife assembly holder in accordance with the present invention may be attached to a mounting rod by hand, without the use of tools. A knife assembly holder in accordance with the present invention allows a knife assembly to be mounted on a mounting rod and adjusted in position thereon by an operator quickly and easily while a bean snipper or similar device with which the knife assembly is used is in operation.
A knife assembly holder in accordance with the present invention includes two complementary plate members. Each of the first and second complementary plate members has a first end and a second end. A structure is formed at the first end of each of the first and second plate members so as to allow the first ends of the first and second plate members to be moveably joined together, e.g., in a hinged relation. For example, the first end of the first plate member may include a tab formed thereon which extends into a corresponding slot formed on the first end of the second plate member, thereby to join the first and second plate members together in a hinged relation. The first and second plate members are shaped such that, when the first ends thereof are joined together, the plate members may be closed about the structure formed at the first ends thereof to bring the second ends of the plate members together, such that the joined plate members together form an opening which is sized so as to receive a mounting rod upon which the knife assembly holder is to be mounted. The opening thus defined by the two plate members, when closed together around a mounting rod, is sized and shaped such that an inner surface of each of the plate members contacts an outer surface of the mounting rod at a plurality of contact points.
A tightening structure is provided at the second ends of the plate members, where the second ends of the plate members come together. The tightening structure is adapted to pull the second ends of the first and second plate members together. For example, the tightening structure may be implemented as a hand turnable threaded knob which includes a threaded shaft which extends through apertures formed in the second ends of each of the plate members into the threaded aperture of a nut or other threaded structure formed or positioned on the second end of one of the plate members. As the hand turnable knob is threaded into the nut, or other structure, the second ends of the plate members are brought tightly together. When the plate members are positioned about a mounting rod to which a knife assembly is to be mounted, tightening of the threaded knob in this manner brings the second ends of the plate members together, thereby pulling the plate members tightly against the mounting rod at the plurality of contact points, thereby to mount the knife assembly holder securely to the mounting rod. A more conventional nut and bolt assembly without a hand turnable knob may be used to implement the tightening structure, although such a device would require the use of a wrench or other tool to tighten the plate members to the mounting rod.
A knife assembly, e.g., a snipper knife assembly for a bean snipper, or similar device, to be mounted to a mounting rod using a knife assembly holder in accordance with the present invention, includes a knife head, with sharpened knife edges formed thereon, mounted, e.g., on a resilient flexible knife rod. The knife assembly is mounted to the mounting rod using the knife assembly holder of the present invention by providing knife rod apertures through one of the knife assembly holder plate members. The knife rod of the knife assembly is inserted through the knife rod apertures. The knife rod apertures formed in the plate member are positioned thereon such that the knife rod of the knife assembly extends through the plate member in a direction perpendicular to the axis of the mounting rod upon which the knife assembly holder is mounted. A knife rod stop may be formed on the knife assembly holder which assists in positioning the knife rod to extend by a proper amount through the knife rod apertures. The knife rod apertures formed in the plate member are also positioned thereon such that, when the resilient knife rod is extended through the knife rod apertures of the plate member of a knife assembly holder mounted on a mounting rod, a portion of the resilient knife rod is positioned by the knife rod apertures adjacent to the mounting rod. On either side of this contact point between the resilient knife rod and the mounting rod, the resilient knife rod is in contact with a surface of the knife rod apertures formed in the plate member. As the tightening structure, mounted on the second ends of the plate members, is tightened, the plate member through which the knife rod apertures are formed is pulled toward the mounting rod on which the knife assembly holder is mounted, thereby pulling the resilient knife rod, captured in the knife rod apertures formed in the plate member, against the mounting rod at the contact point between the resilient knife rod and the mounting rod. This securely pinches the resilient knife rod between the apertures formed in the plate member and the mounting rod, thereby securing the knife assembly in a desired position.
The present invention thus provides a knife assembly holder for a bean snipper or similar agricultural product processing device which allows a snipper knife to be mounted to a bean snipper or other device, adjusted in position thereon, and removed therefrom, easily and quickly by employing a single tightening structure, such as a hand turnable threaded knob. A knife assembly holder in accordance with the present invention may be used to mount a snipper knife assembly to a mounting rod positioned adjacent to a bean snipper drum by simply closing the two plate members of the knife assembly holder about the structure formed on the first ends thereof around the mounting rod, such that the plate members contact the mounting rod at several contact points. The knife rod of a snipper knife assembly is then inserted through the knife rod apertures formed in one of the plate members, such that a portion of the knife rod is adjacent to the mounting rod. The knife rod stop ensures that the knife rod is extended through the knife rod apertures by the proper amount. The tightening structure, e.g., the hand turnable threaded knob, mounted on the second ends of the plate members, is then tightened, thereby bringing the second ends of the plate members together to both tighten the plate members themselves to the mounting rod as well as to pinch the knife rod securely between one of the plate members (at the knife rod apertures formed therein) and the mounting rod, thereby securely mounting the snipper knife assembly in position to the mounting rod. To adjust the position of the knife assembly, the single tightening structure, e.g., the threaded knob, is simply loosened, thereby releasing the pressure between the knife assembly holder plate members and the knife rod and the mounting rod, thereby allowing the two plate members forming the knife assembly holder to be rotated in position about the mounting rod, to, thereby, for example, adjust the amount of pressure of the knife edges formed on the head of the knife assembly against, e.g., the outer surface of the rotating drum of a bean snipper, or to allow the position of the knife assembly in the knife rod apertures to be adjusted, or to allow a new knife assembly to be inserted into the knife rod apertures. The tightening structure may then be tightened once again, to secure the knife assembly back into the desired position. To entirely remove a knife assembly holder from the mounting rod, the tightening structure, e.g., the hand turnable threaded knob, may simply be unthreaded from the second ends of the plate members, the knife assembly removed from the knife rod apertures, and the plate members opened about the structure formed at the first ends thereof, thereby to separate the second ends of the plate members such that the knife assembly holder may be removed from the mounting rod.
These and further objects, features, and advantages of the present invention will be apparent from the following detailed description, taken in conjunction with the accompanying drawings.